Primary: SQL Server Error 5171

SQL Server Error 5171

This article answers the user query, i.e. SQL Server Error 5171

If you have a similar query, don’t worry; in this article, we are going to discuss how to fix SQL Server error 5171. Also, we are mentioning the ways to perform this operation.

It looks like the MDF file is corrupted or not recognized. If you have a database backup it is used for the existing backup to restore the database. and after the upgrading SQL Server attach the database using the sp_attach_db command if can’t attach the previous database. 

And so very common issue is cookie-like database corruption, which affects the MDF  files, here is its result below.

Why Does 5171 Error in SQL Error Code Happen?

An MDF file is saved, and the size of each page in it is only 8KB. The first page of the MDF file contains only the header and some additional information, such as the signature and file name. The current data is stored in the remaining pages. If the header page and the other pages are not identified due to the size issues, the MDF file will not be considered valid.

Then this situation causes an error 5171 in SQL Server 2008/2000/2005/2016/2017. If this same problem persists. And it can arise due to failure, damage, drivers, etc.

How to Resolve SQL Server Error 5171 MDF is Not a Primary Database File

Here we resolve the issue of how we can fix SQL Server error 5171 if the MDF file is not a primary database so in this situation we discussed two scenarios where SQL Server happens.

 If you run SQL Server and create two files with the same name and database, then the SQL Server will become confused and unable to decide which one to update. When using SQL Server, you must build a single database online in order to prevent confusion.

Here are the solutions to fix the Mirrored Database

  1. Firstly, configure the database.
  2. Using the ALTER DATABASE MODIFY FILE command to update the MDF files.
  3. After the update stop the current SQL Server.
  4.  Now copy the MDF and LDF files on another directory.
  5. At last restart the server and then attach the MDF and LDF files.

Upgrade Incorrect SQL Server 

In this case, you need to update the SQL Server version first. If you don’t update it, the file will not be supported, showing an error. After upgrading the SQL Server, try attaching the MDF file again and see if the new version supports this file. Suppose it doesn’t, try repeatedly until successful.

This situation will help you to resolve the SQL Server Error 5171 by running the sp_attach_db command.

Here Are Some Critical Limitations while Executing Manually

Step 1: The user needs a lot of time to solve error 5171.

Step 2: A manual solution does not guarantee the resolution of error 5171; it does not assure the user that this error will be resolved.

Step 3: If not performed safely or carefully, this could lead to data loss and damage. For this user needs a technical expert to fix SQL Server error 5171.

Note: Remove these drawbacks, it’s advised you involve an experienced database administrator or SQL Server expert, please take a regular and timely backup, and follow the best instructions, while fixing the error user may know that carefully execute troubleshooting steps after a thorough analysis.

Fix SQL Error 5171 Step by Step Automatically

fixing SQL Server Error 5171 through a manual solution is very difficult for non-technical users, so in this case, users can go with a professional tool Software SysTools SQL Recovery Tool. With this tool, users can easily resolve the issue without any hassle, and there won’t be any problems. The tool also provides easy-to-understand and detailed steps for the process.

With the help of this tool, users can scan and restore all the data like triggers, tables, stored procedures, etc.

Below Here are the Steps for Professional Tools to Fix SQL Server Error 5171:

  1. Install the software in your systems.
  1. Now click on the open button to add the MDF file.
  1. In the scan options, there are two modes quick scan and advanced scan.
  1. Set the desired location to export the data.
  1. Last click on the export button to fix SQL Server error 5171.


In this article, we have learned about SQL Server Error 5171. We discussed that the database can be clashing because of the database mirroring. And in-depth we discussed why the size of the file is incorrect in SQL Server error. If manual solutions seem difficult, non-technical users can opt for automated tools for a quicker and easier fix. Automated tools are user-friendly and perform the task swiftly. I hope this blog will help you to resolve the query.


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